Noninvasive bioluminescence imaging of the muscle-specific myomiRs-206, −133 and −1 in mice. Eight micrograms of pRILES/122T, pRILES/133T, pRILES/1T and pRILES/206T were formulated with the 704 amphiphilic block copolymer and intramuscularly injected in the left and right tibialis anterior to transfect the skeletal muscles of Swiss mice. Negative control included the pRILES, not regulated by miRNA. Bioluminescence imaging was performed 6 days later and light emission quantified using ROIs covering the lower legs of the mice. (A) Representative bioluminescence images collected in the left lower legs of mice. (B) Quantitative bioluminescence values detected in the mice described in A and expressed as luciferase induction relative to the control pRILES group of animals set arbitrarily to the value of 1. (C) Quantitative RT-PCR analysis of myomiR expression detected in the tibialis anterior muscles of another group of mice. (D) Absolute quantification of plasmid content in the skeletal muscle of the mice described in A. (E) Quantitative RT-PCR analysis of CymR expression in the skeletal muscle of one representative scanned mouse described in A. Results are expressed as CymR fold change relative to control pRILES-tissues set arbitrarily to the value of 1. Error bars in B, mean ± SEM (n = 6) of one representative experiment repeated at least three times. Error bars in C, D, E, mean ± SD (n = 3) of one representative experiment repeated at least three times. Statistics by the two-tailed t-test, *P < 0.05; **P < 0.01 n.s (no statistically significant difference) compared with the pRILES control group.